Tester denounced Franken and said that the Minnesota senator had donated $25,000 to Tester's campaigns. Both Tester and Franken are Democrats.

Franken has been accused of groping and forcibly kissing a woman in 2006. Franken has apologized and requested an ethics investigation into his conduct.

The Billings Gazette reports that Tester will donate $25,000 to the Montana Coalition Against Domestic and Sexual Violence.

Tester is up for re-election in 2018.

Franken also has given $12,500 to the Montana Democratic Party since 2011, but party spokesman Roy Lowenstein says the money has already been spent and so the party would not be making donation arrangements similar to Tester's.